<template>
  <div class="swiper-container">
    <div class="swiper-wrapper">
      <div class="swiper-slide" v-for="(item , index) in skuImageList" :key="item.id">
        <img 
          :class="{active: index === defaultIndex}"
          :src="item.imgUrl" 
          @click="changeIndex(index)"/>
      </div>
    </div>
    <div class="swiper-button-next"></div>
    <div class="swiper-button-prev"></div>
  </div>
</template>

<script>
import Swiper from 'swiper'
import "swiper/css/swiper.min.css"
export default {
  name: "ImageList",
  props: ["skuImageList"],
  data() {
    return {
      defaultIndex: 0
    }
  },

  methods: {
    //点击缩略图逻辑
    changeIndex(index){
      //修改自己的样式
      this.defaultIndex = index

      //把下标传给大图片
      this.$bus.$emit("changeBigImg" , index)
    }
  },

  watch:{
    //监听轮播图数据
    skuImageList:{
      immediate: true,
      handler(){
        if(!this.skuImageList.length) return
        this.$nextTick(() => {
          new Swiper(".swiper-container", {
            direction: "horizontal", // 垂直切换选项
            // loop: true, // 循环模式选项
            slidesPerView: 4,
            slidesPerGroup: 1,

            // 如果需要分页器
            pagination: {
              el: ".swiper-pagination",
            },

            // 如果需要前进后退按钮
            navigation: {
              nextEl: ".swiper-button-next",
              prevEl: ".swiper-button-prev",
            },
          });
        })
      }
    }
  }

};
</script>

<style lang="less" scoped>
.swiper-container {
  height: 56px;
  width: 412px;
  box-sizing: border-box;
  padding: 0 12px;

  .swiper-slide {
    width: 56px;
    height: 56px;

    img {
      width: 100%;
      height: 100%;
      border: 1px solid #ccc;
      padding: 2px;
      width: 50px;
      height: 50px;
      display: block;

      &.active {
        border: 2px solid #f60;
        padding: 1px;
      }

      &:hover {
        border: 2px solid #f60;
        padding: 1px;
      }
    }
  }

  .swiper-button-next {
    left: auto;
    right: 0;
  }

  .swiper-button-prev {
    left: 0;
    right: auto;
  }

  .swiper-button-next,
  .swiper-button-prev {
    box-sizing: border-box;
    width: 12px;
    height: 56px;
    background: rgb(235, 235, 235);
    border: 1px solid rgb(204, 204, 204);
    top: 0;
    margin-top: 0;
    &::after {
      font-size: 12px;
    }
  }
}
</style>